Thanks so much for the info!!
The kribs are being a little nippy but I'll keep an eye on them. So far it's not too bad and they do seem to be sticking close together.
The CPDs are in a tank on their own. Just a nano with 4 of them atm though I might get 2 more as I read that 6 is the usual smallest group. I'll be careful about the food, wouldn't have thought of any of that so definitely thanks for the heads up!!